The effect of the quality of ammonium nitrate on the properties of emulsion explosives

Abstract

Emulsion explosives are widely used in the mining industry, and their use, in combination with modern means of initiation, has improved the safety of mining operations and significantly increased labor productivity. The main component of emulsion explosives is ammonium nitrate, which is part of the emulsion matrix. Grade A is produced for the industrial purposes, while Grade B is used in agriculture. Due to difficulties in logistics, mining enterprises that produce emulsion matrix often use Grade B ammonium nitrate. The main disadvantage of ammonium nitrate is its high water absorption capacity. Caked ammonium nitrate loses its properties, becomes unusable and cannot be utilized in preparation of the emulsion matrix. In order to slow down the caking process, special additives are introduced into the composition of Grade B ammonium nitrate. The paper presents the research data on the material composition of ammonium nitrate of Grades A and B as well as its influence on the physical properties of the obtained emulsion matrix. To identify differences in the physical properties of the emulsion matrix obtained from ammonium nitrate of Grades A and B, studies of the dynamic viscosity and electric capacitance of emulsions were carried out, and the detonation velocities of emulsion explosives charges were measured. It has been established that Grade B ammonium nitrate contains sulfates, exceeding the threshold values of which can lead to partial or complete stop of detonation of the emulsion explosive; dynamic viscosity and electrical capacitance of the emulsion matrices with Grade B ammonium nitrate are characterized by low rates; the detonation rate of the charge prepared using Grade B ammonium nitrate is 7–10% lower than the detonation rate of the charge based on Grade A ammonium nitrate.